# In the figure, you see the frame of a lampshade. It is to be covered with a decorative cloth.

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In the figure, you see the frame of a lampshade. It is to be covered with a decorative cloth. The frame has a base diameter of 20 cm and height of 30 cm. A margin of 2.5 cm is to be given for folding it over the top and bottom of the frame. Find how much cloth is required for covering the lampshade. ## 1 Answer

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Here, r = 20/ 2 cm = 10 cm

Height = 30 cm

Circumference of the base of the

frame = 2πr

= 2π × 10 cm = 20π cm

Height of the frame = 30 cm

Height of the cloth needed for covering the frame

(including the margin) = (30 + 2.5 + 2.5) cm = 35 cm

Also, breadth of the cloth = circumference of the base of the frame.

∴ Area of the cloth required for covering the lampshade = length × breadth

= 35 × 20π cm2 = 35 × 20 × 22 7 cm2 = 2200 cm2 Ans. 0 votes
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